1. Field of the Invention
The present invention relates to control devices, and in particular those that are illuminable in combination with being able to sense both touch and rotary motion.
2. Description of the Related Art
Modern mixing consoles tend to include digital control of various parameters. This can in part be due to the actual parameters being controlled being those of digital devices, or as part of a general market trend towards the use of digital circuit elements to provide power savings, cost savings and reduction in complexity, etc.
One major advantage of digital control elements such as sliders, knobs and buttons in mixing consoles is that it is much easier to assign different functions to the control elements than with analogue controls. This tends to be because the digital control elements are all connected to a bus under the control of a common microcontroller. The assigned function tends to be indicated by the appearance of the control or some type of indicator near it. Color is often used, with mixing consoles manufactured by the present applicant having different color controls in the equalizer sections for different frequency bands.
A fundamental building block of rotary controls in mixing consoles, typically used for controlling equalizers, etc. that have digital control is the rotary encoder. These are electro-mechanical devices which convert the angular position or motion of a shaft into an electrical code. Absolute encoders indicate the current position of the shaft, whilst incremental encoders provide information about the motion of the shaft. The position and speed of the shaft can then be derived. Some rotary controls are touch sensitive, so that for example automated processes, for example attenuation applied to a particular frequency band in an equalizer, can be interrupted to give way to manual control.
A problem encountered is the combination of maintaining touch sensitivity and providing the capability of the control to change appearance to indicate an assigned function for example, whilst also providing other features to allow the rotary control to be configurable for controlling a multiplicity of different kinds of parameters.